Save and load the day

using System.Text.Json;
using System.Text.Json.Serialization;
using Kallamo.Umwelt;
using var engine = UmweltEngine.Create("deepmoor.umw");
const string projectId = "deepmoor";
var provenance = Provenance.Human();
var json = new JsonSerializerOptions
{
    DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull,
    Converters = { new JsonStringEnumConverter(JsonNamingPolicy.KebabCaseLower) },
};
void Print(string label, object? value) => Console.WriteLine($"@@{label}\n{JsonSerializer.Serialize(value, json)}");

// The world, declared once: sending the same manifest again changes nothing.
engine.WorldEnsure(new EnsureWorldInput
{
    Project = new WorldProject { Id = projectId, Name = "Deepmoor", Timescale = "day" },
    EntityTypes = new()
    {
        new WorldEntityType { Id = "person", Name = "Person", Kind = EntityKind.Agent },
        new WorldEntityType { Id = "place", Name = "Place", Kind = EntityKind.Other },
    },
    Entities = new()
    {
        new WorldEntity { Id = "wren", TypeId = "person", Name = "Wren, the player" },
        new WorldEntity { Id = "bandit", TypeId = "person", Name = "The bandit" },
        new WorldEntity { Id = "bridge", TypeId = "place", Name = "The old bridge" },
        new WorldEntity { Id = "river", TypeId = "place", Name = "The river" },
    },
    Predicates = new()
    {
        new PredicateDef { Id = "collapsed", Label = "collapsed", Object = ObjectKind.None, Cardinality = Cardinality.One },
        new PredicateDef { Id = "flooded", Label = "flooded", Object = ObjectKind.None, Cardinality = Cardinality.One },
        new PredicateDef { Id = "is-named", Label = "is named", Object = ObjectKind.Value, Cardinality = Cardinality.One },
    },
});
var collapsed = Claim.Unary("bridge", "collapsed");
var flooded = Claim.Unary("river", "flooded");
var banditName = Claim.Value("bandit", "is-named", "Ressa");
// What Wren sees becomes canon and her own knowledge of it, at the scene that holds them.
List<RecordInput> Sees(string id, Claim seen, string eventId) => new()
{
    Records.Fact(seen, id: $"fact-{id}"),
    Records.Knows("wren", seen, Acquired.Witnessed(eventId), id: id),
};
CommitOutcome Scene(string timelineId, string id, string title, long tick, List<RecordInput> records) => engine.Commit(new CommitInput
{
    ProjectId = projectId, TimelineId = timelineId, AttemptId = id,
    Event = new EventInput { Id = id, Type = "scene", Title = title, Position = Position.At(tick), Participants = new() { "wren" }, Provenance = provenance },
    Records = records,
});
bool WrenKnows(Claim claim, string timelineId) =>
    engine.Holds(new HoldsPayload { ProjectId = projectId, TimelineId = timelineId, Holder = "wren", Claim = claim }).HoldsAs == HoldsAs.Same;
// Morning of day 12: the day is a draft. Nothing in it counts until Wren sleeps.
engine.TimelineOpenDraft(new OpenDraftInput { ProjectId = projectId, Id = "day-12", Label = "Day 12" });
Scene("day-12", "bridge-down", "The bridge is gone", 12, Sees("wren-bridge", collapsed, "bridge-down"));

// An ambush on the road: a draft inside the day. Wren falls, and the player reloads it.
engine.TimelineOpenDraft(new OpenDraftInput { ProjectId = projectId, Id = "ambush-1", Label = "Ambush, first try", BaseTimelineId = "day-12" });
Scene("ambush-1", "ambush", "Ambush on the road", 12, Sees("wren-name", banditName, "ambush"));
Print("midday", new
{
    bridgeOnMain = WrenKnows(collapsed, "main"),
    bridgeInDay = WrenKnows(collapsed, "day-12"),
    nameInDay = WrenKnows(banditName, "day-12"),
    bridgeInAmbush = WrenKnows(collapsed, "ambush-1"),
    nameOnMain = WrenKnows(banditName, "main"),
    nameInAmbush = WrenKnows(banditName, "ambush-1"),
});
engine.TimelineDiscard(new DiscardPayload { ProjectId = projectId, TimelineId = "ambush-1" });
// The second try replays the same scene, with the same ids. A discarded draft still holds them.
engine.TimelineOpenDraft(new OpenDraftInput { ProjectId = projectId, Id = "ambush-2", Label = "Ambush, second try", BaseTimelineId = "day-12" });
try
{
    Scene("ambush-2", "ambush", "Ambush on the road", 12, Sees("wren-name", banditName, "ambush"));
}
catch (ConflictException error)
{
    Print("replay-refused", new { code = error.Code });
    Print("purged", engine.TimelinePurge(new TimelineRef { ProjectId = projectId, TimelineId = "ambush-1" }));
    Scene("ambush-2", "ambush", "Ambush on the road", 12, Sees("wren-name", banditName, "ambush"));
}
engine.TimelinePromote(new TimelineRef { ProjectId = projectId, TimelineId = "ambush-2" });
// Meanwhile the world kept turning on main: the river flooded. When Wren sleeps,
// the day cannot be promoted over a main it has not seen.
Scene("main", "flood", "The river floods", 12, new() { Records.Fact(flooded, id: "fact-flood") });
try
{
    engine.TimelinePromote(new TimelineRef { ProjectId = projectId, TimelineId = "day-12" });
}
catch (VersionConflictException error)
{
    Print("sleep-refused", new { code = error.Code, details = error.Details });
    var rebased = engine.TimelineRebase(new TimelineRef { ProjectId = projectId, TimelineId = "day-12" });
    Print("rebased", new { baseVersion = rebased.BaseVersion, headVersion = rebased.HeadVersion });
    engine.TimelinePromote(new TimelineRef { ProjectId = projectId, TimelineId = "day-12" });
}
Print("after-sleep", new { bridge = WrenKnows(collapsed, "main"), name = WrenKnows(banditName, "main") });
// Day 13: the player quits without saving. Discard and purge, and main never saw it.
engine.TimelineOpenDraft(new OpenDraftInput { ProjectId = projectId, Id = "day-13", Label = "Day 13" });
Scene("day-13", "ford", "The flooded ford", 13, Sees("wren-flood", flooded, "ford"));
var quit = engine.TimelineDiscard(new DiscardPayload { ProjectId = projectId, TimelineId = "day-13", Purge = true });
Print("quit", new { status = quit.Status, purged = quit.PurgedAt is not null, floodOnMain = WrenKnows(flooded, "main") });
Print("timelines", engine.TimelineList(new TimelineListPayload { ProjectId = projectId }).Select(t => new
{
    id = t.Id, parent = t.ParentTimelineId, status = t.Status, depth = t.Depth, purged = t.PurgedAt is not null,
}));